PRISTINA, Kosovo — When Beriane Mustafa returned home from school 16 years ago, she encountered a crowd outside her apartment and was shocked to learn that her father, a prominent journalist and political adviser, had been assassinated.

Xhemajl Mustafa's death haunts her to this day. “You wake up in the morning with that question mark over your head that says ‘Who did it and why?’” said Mustafa, 35. “That is what, on a daily basis, is killing you.”